Rock-drill.



Patented Nov. l2, l90l.

H. D. GRIPPEN, G. WHITE &. G. S. MAXWELL.

R 0 G K D B l L L.

' (Application filed Dec. 31, 1900.)

5 Sheets-Sheet I.

(No Model.

f n 1: mmm m CH Y B u R Q m Q \ll.

, b m n my w 4 J6 No. 686,444. Patented Nov. l2, i901. H. D. CRIPPEN, G.WHITE 8.. G. S. MAXWELL.

R U C K D R L L (Applicatiin filed De 5 Sheets-Sheet 2.

(No Model.)

Nu.'686,444. y Patel lted Nov. I2, 1901. H. n. CRIPPEN, a. wnmz &. a. s.MAXWELL.

' ROCK DRILL.

(Application filed Dec. 81, 1990.) (No Model.) A 5 Sheets8heet 3.

ATTORNEY.

No. 686,444. I Patented Nov. l2, I901.

H. D. GRIPPEN, G. WHITE &. G. S. MAXWELL. RUCK'DRILL.

' (Application filed Dec. 3 1, 1900.)

' (No Model.) k 5 Sheets-Sheet 4.

v Patented Nov. [2, mm. H. D. CRIPPEN, G. WH|TE & G. s. MAXWELL.

ROCK DRILL.

(Application flled Dec, 31, 1900.) I (llo Model) 5 SheetsSheei 5.

HENRY D. oRiP'PnN, or NEW YORK, :N'. :Y.,"A ND csonen WHITE-AND.

GEORGE s. MAXWELL, or JERSEY'CITY, NEW JERSEY; SAID wnrri r ANDMAX-WELLASSIGNORS 'ro SAID ORIPPEN.

' ROCK-DRILL.

SPECIFICATION forming part of Letters Patent 1\l0. 686,444, datedNovember 1'2, 1801.

Application filed December 31, 1900. seen No. 41,551. (No mast),

To aZZ whom itmay concern:

Be it known that we, HENRY D. CRIPPEN, of New York city, county andState of New York, and GEORGE WHITE and GEORGE S. MAX- WELL, of JerseyCity, in the county of Hudson,in the State of New Jersey, have in ventednew and useful Improvements in Rock-Drills, of which the following,takenin connection with the accompanying drawings, is a full, clear,and'exact description.

This invention relates to a rock-drill of the percussive type and is aunitary device complete in itself, with all the parts inclosed in asingle compact case. It consists, essentially,

of two elements, the motor element or motor. and the drill element ordrill,- the motor main:

taining a fixed position in the case, while the drill is fedindependently on interior feedways formed in the case itself. Thisrockdrill 'is designedparticularly for an electric motor, to which thecurrent may be brought.

fromfa'ny convenient distance through the usual line-wires. In anyposition of the drill element power is communicated thereto from gbetween the field-magnets. By a simple ad aptation of the partsasingle'motor may be combined to operate'two drill elements in a singlecase, the drill elements being operated independently or together,simultaneonslvor alternately; 3

The important details of our rockdrill are the integral case inclosingthe magnets and the suitably-.journaled armature having an integralextension or extensions provided with ways for the drill elementorelements comprising the bit, ram, spring .or springs, operative cams,shells inclosing the respective cams, and means for rotating the bit afixed dist-anceat' each stroke independent of the lengthiof the stroke.A single crank is used, adapted in one position, through one set ofconnections, to vary the distance between the cams and to turn on thecurrent'at-tho proper time through a convenient arrangement ofelectrical connections, andina sec ond position, through a second set ofconnections, to feed the drill in and out. The con1 plete rock-drill issuitably supported with a low center of gravity on a special base,insuring stability and permitting'thebit to boremoved convenientlywithout afiecting the alinement. Most of these improvements may be usedwith other than electrical power. Y

Our invention is shown in the accompanying drawings, in which the samereference letters and numerals indicate thesame parts in all thefigures.

Figure I is a longitudinal'sectionofourk complete rock-drill, portionsbeing shownin elevation and being broken away. Fig. II is a portion ofFig. Ienlarged, showing the drillshell fed forward a short distance andthe main cams separated. Fig. III is an enlarged elevation of. a portionof Fig. II, showing a preferred form of the" mechanism for rotatablyshifting the bit positively at each stroke. Fig. IV is a more extendedview of same mechanism, showing parts in' section.- 'Fig V is similar toFig. IV, with the main caims removed. Fig. VI is a front elevation of:the rock-drill, showing the handles. Fig. =YI'Lis a'top plan'view of aportion of the rear rojection and the. electric switch. Fig. VIIIis arear elevation of a;portion: of the rea'rprojection with the lowerrplateremoved to show the electrical switching mechanism; Fig. IX is a sideelevation of the electrical mechanism shown in Fig. VIII, taken at anangle of about forty-five degrees and showing the inclosing shell 'andshafts in section and the lower plate in position. Fig. X shows vinsection the screw-stud and connected .parts by which the contact-pieceisshifted to turn on the cu'r-' I rent.. Fig. XI is a diagram of; theelectrical switching mechanism; FigiXII' is a diagrammatic elevation ofthe rock-drill re- 5 duced, showing the base-plate and meansfor swingingthe drill to one side or thejother thereon to remove the bit. Fig.Xnri'isa 6gp plansview of the base-plate; FigsuXIV 'to XVIII show amodification in form of our single rock-drill, in which by a simplevariation of the parts and the addition of connections two drills ordrilling elements may be combined with a single motor in one case. Thesefigures do not show all of the parts in detail, but are substantiallydiagrams illustrating the changes in form and the new parts. Fig. XIV isa top plan view, with portions broken away, of the double drillsupported on a quarry-bar of usual construction. Fig. XV is a rearelevation of the preceding view with the rearplate removed. Fig. XVIisaside elevation of Fig. XV. Fig. XVII is a top plan view of a portionof Fig. XV enlarged. Fig. XVIII is a corresponding bottom plan. Figs.XIX and XX are plans of parts relating to the bit-rotating mechanism.

Inclosing case, motor, and drill.A is the main case or motor-caseinclosing the motor, of which E is the armature, C O the fieldmagnets,and D the commutator.

E is a rear projection on the motor case, forming a chamber for themechanism through which the current is controlled from the crank F.

G is the upper plate, removable for repairing the motor, attaching thebrushes,&c., and H the lower rear plate on the rear projection coveringthe mechanism in the chamber.

J is a part of the case and is an extension integral therewith orsuitably secured thereto, and is provided with ways K K, on which is fedby the feed-screw L, engaging with nut M, thedrill-shell N, carrying thebit 0, the ram P, the ram-cam Q, the driving-cam R, and the other partsby which the bit is operated and its motion controlled.

S is the rear plate on the drill.

1 is the nut for securing the bit in the chuck 2, screwcd'to the outerend of the ram P against the hollow collar 3, keyed fast to the ram andhaving the flange 4, fitting the outer end of the drill-shell N. \Vithinthe drillshell end is screwed the nut 6, serving as a bearing for thecollar 3 as it oscillates with the ram and also as aseat for the weakerbuffer-spring 5, retained between it and collar flange 4. Between thecollar and the septum 7, provided with an antifriction ball-bearing 8,if desired, for the turn of the hit, is arranged the main or percussivespring 9, al-

ternately compressed by the action of the' main cams as the ram and bitare retracted and expanding when the cams disengage to effect the blowor stroke of the bit.

By the following mechanism the drivingcam R is rotated against theram-cam Q, fixed on the ram. 11 is the armature tubular shaft carried inbearings 12 12, capable of a certain amount of self-adjustment andhaving oilwells 13 13 and oil-rings. To this shaft by elongated feather14 is keyed the telescoping driving-shaft 15, rotating therewith, butfeeding in and out as the drill shellis fed forward and back. To shaft15 is fixed pinion 17, meshing with intermediate quill-pinion 18 on stud19, which meshes with gear 20 on driving-cam shell 21, keyed to itsdriving-cam R by feather 22, so that they rotate together; but thedriving-cam is free to move longitunally within its shell a sufficientdistance to permit the entire separation of the two cams when startingthe drill to regulate the length of the stroke. The driving-cam shell 21is retained against longitudinal movement by collar 23, resting againstrib 16 of drill-shell, and escapement-ring 24, bolted to shell, and isprovided with a shoulder 25 and shank 26, to which is fitted the nut27,1ocking it to move longitudinally with the separating-shell 28,threaded to 29 to engage with the drillcase, on which it is moved in andout to sepa rate the cams more or less. This separatingshell has theexterior gear 53, to be described. Within the separating-shell 28rotates the driving-cam and its shell, ball-bearing 30 being interposed,if desired.

Bit-rotating parts- T0 rotate the bit and shift the position of itscutting edge at each -successive stroke, the driving-cam shell2lisprovided on its rear shoulder with the small gages at each rotation withsmall cam 32, having one inclined edge and an elongated face on ram-camshell 33, which is rotatably connected by feather 34 to the ram-cam Qand is provided with the cam-groove 35, with which engages one or morepins 36, fixed in a fixed portion of the drill-case, such as theescapement-ring 24. At each rotation of the driving-cam R these smallcams engage, by which the ram-cam Q is turned and would be continuouslyrotated, but that the ram-cam shell 33, rotating therewith, turns on thepins 36, in engagement with its cam-groove 35, and this groove beingformed with a series of inclines the shell 33 is carried rearwardly byengagement of pin 36 with each incline a sufficient distance todisengage the small cams, when rotation of bit ceases and it is free todeliver a straight blow, the small cams being so arrangedas to engagewhen the bit is retracted-that is, during engagement of inclined edgesof main cams-when the spring is being compressed. The small cams shouldbe arranged to disengage at the same time as the main cams. Thus at eachrotationof the driving-cam the bit is rotated through a short are of alength fixed by the number of in- ,clines in the cam-slot 35, and theshift of bit is always constant and of a constant length of are, whetherthe stroke be long or short. Spring 38 tends to force the ram-cam shellforward to insure engagement of these small cams.

The described bit-rotating mechanism is shown in Figs. I and II; but inFigs. III, IV, V, XIX, and XX is shown a similar but preferred formthereof. In this better form ram-cam Q is rotatably keyed as before byfeather 34 to ra m-cam shell 33, here made in two parts A and B (securedtogether firmly by thread and shoulders or other suitable means) forconvenience in cutting inclined cam 31, having one edge inclined, whichen-' ratchet-teeth C,en gaging with corresponding opposite ratchet-teethD on shifting shell E (shown in plan in Fig. XX) and formed with notchesF on its rear flange G to engage fwithslightly-smaller studs H on someplate, as J, fixed in drill-shell and shown in Fig. XIX. Spring orsprings K, arranged in sockets in part A or in other suitable position,tend to force ram -,cam shell 33 forward. Spring L is arranged aroundshifting shell E, with ends M and N engaging, respectively, withdrill-shell andv'shifting shell, as hole P, in flange. The operation isbest shown in Fig. IV, where the main cams are about to disengage andram-cam shell has been forced rearwardly by engagement of small cams 31and 32, so that teeth 0 engage with teeth D and slide along theirinclined edges, thus turning ram and bit a short distance. Theengagement of the cams tends to turn the shells, which is stopped by theengagement ofthe teeth and notches'F on studs H after shifting shell hasbeen-turneda short distance, and when shells and-teeth disengageshifting shell is returned by springL to its normal position, turningthe teeth D back past teeth 0 in position shown in Fig. III, whereengagement is certain.

Crank and c01mec'ti0ns.-At the rear of the motor-case is journaledthecrank F on the tubular crank-shaft 40, carrying pinion 41 on its innerend and fitted to stud 42, having grooves. 43 4-3, with whichengageslatch 44 to lock crank in its out or in'position. By means of thissingle crank in its out position the cams are separated before the motorcan be started, thus guarding the motor against overloads at startingand blown fuses.

The current is then gradually turned on through intermediate mechanism,to be described. A The crank is then reversed to move the cams intoengagement to a greateror less extent-towregulate the length ofthestroke. The crank isthen moved into its in position to feed the-drillthrough following connections: In out position of crank. Fpinion4lengages with rear gear 45 on solid shaft 46, rotatably connected totelescoping tubular shaft '47 by elongated feather 48. Front gear 49,keyed fast to.- front end of tubular shaft 47, meshes with elongatedintermediate gear 51 of such length as tonresh with gear 53 onseparating shell 2.8 in any suitable position in which .the lattermay-be adjusted forward or back'in the drill-shell,;carrying with it thedrivingcam R. Having separated the cams by back turn of the crank-andturned on the current by a continuou'sback turn, as here arranged, thecrank'jis reversed to bring the cams intogreater,or: less-engagement,and thus regulate tlielle'ngth of the stroke from minimum. tofullstroke; The spring-latch is then released, the crank pushed in onstud 42, bringing pinion 41 into engagement with rear pinion 55 on outertubular shaft 56 in bearings 57 57, and carrying front pinion 58 onfront end, by which, through intermediate pinions chamber of projectionE is arranged parallel to thevplate of the motor-case a supportingplate70, of slate or other insulating material, carrying the electricalconnections and controlling mechanism. In this base-plate is journaled afiber-gear a, meshing with gear 45 and fixed on screw-stud'b', on whichis'fitted to turn freely the fiber clutch-collar c, having the pawl 01and clutch member j pinned to it by pin 2. Fitted to the screw-stud b isthe clutch-nut e, moving on the screw-stud b as it is turned by its geara, but prevented from rotating by featherf engaging in spline ginguard-case h, secured'to base-plate 7 O,and to clutch-n ut eby pins u toengaging in groove v is vthe opposite clutch member 1 having feather wengaging with spline won stud b,

so as to turn freely on clutch-nut and rotate with stud to turnclutch-collar 0 when the clutch members engage. These clutches arepreferably metallic and. insulated. When gear a has been rotated acertain number of times in a rearward direction, ashere shown, theclutch-nut e, moving along the screwstud b, will force the clutchinemberql into engagement with the clutch mem berj, causing the'clutchcollar 0 to rotate with the screw-stub b and by its pawl d to operatethe switch-lever or contact-piece k to close the circuit. The threads onscrew-stud b are so proportioned to the threads 29 on separating-shell28 and to the connecting-gears that the pawl d is only operated "to movethe switch-lever or contact-piecewhen the drivving-cam Ris in forwardpositionand entirely free from theram cam Q to prevent overload, 650.,before armature speeds up, as before stated. The switch-lever is fixedon its shaftm', on which is journaled' the pawl-collar at, having theintegral pawl 0, held in position by spring 19 and lug g on switchleverit. When pawl cl is rotated from right to left it snaps past cam 0, butwhen rotating in the opposite direction it engages therewith and forcesa second cam 0 on cam-collar it against the projection g on switch-lever7t, and moves the switch forward, making contact between terminal 0 andthe successive terminals 8 s .9, cutting out'in succession thearmature-resistance coils R'RC; When the switch has reached its limit ofmovement, the soft-iron block 25, which is pivoted loosely to its end,is brought into contact with the polepiece it of the electromagnet 'uand is held there so long as the electromagnet o is energized. Shouldthe current be cut olf'from this electromagnet, the soft-iron block-i isnot attracted and its switch'is not turned toits original position bythe spring 10 on the switchlever shaft m, thus cutting off the currentfrom the motor. The current to magnet 1' includes in its circuit pawl .rand spring-latch 11 having catch z, engaging with pawl 41:, which isforced outwardly by the spiral spring a, arranged on itg journal b, asshown in Figs. IX and XI.

The magnet 4: may be adjusted by means of the screw (1, jam-nut e,tension-springf, and plunger g toallow only a certain amount of currentto pass through the magnet. Should a greater amount pass, the magnet 2;will be more highly energized, the resistance of the spring f will beovercome, and the armature h on the spring-catch y will be drawn towardthe pole-piece z". This will release the catch 2 from engagement withthe pawl 00 out of contact with the spring-catch y, breaking thecircuit, and thus stopping the motor. The switch-lever is, turning toits original position, rotates the lug j on the switch-lever shaft intoengagement with one end of the insulated rocking lever 7:, whoseopposite end engages a lug m on pawl as, turning it back to engage withcatch .2 on the spring-catch y, thus closing the circuit from theelectromagnet v when it is again desired to start the m'otor.

Any suitable switch 66 may be used for turning on or quickly turning offthe current and stopping the motor, arranged'in any convenient positionon one side of projection, as shown in Fig. VII, where spool forresistancecoils may be secured below it or on the other side, as in Fig.IV. 15' indicates its handle, at its blade, and c p, respectively, itstwo terminals.

The line-wires S S are introduced through a convenient bushing T tobinding-posts U, thence to shaft m of switch-lever and to j ournal b,thence through supplementary magnet and contacts to brushes,resistance-coils R B being arranged'between contacts 8 s s.

Anysuitable means and connections may be used to turn on the currentwhen our drill is operated by electric power; but any-such mechanismshould have the advantages of the mechanism just described-that is, ofturning on the current gradually when the cams are separated, so as toget up speed of the armature before the cams are moved into engagement,making it possible to use a less powerful and lighter motor than wouldbe required to start a rock-drill at once with the cams in engagement.It is also convenient to effect this by a single crank and connectionstimed to operate at the proper time similar to those here described.

XIII. This base-plate is provided on each side with two arms 96 96,having at their upper ends curved lugs 97 97, adapted to fit and receivethe main case when swung to one side or the other and acting. as a stoptherefor when swung clear of the bit in the hole. To the arms are fittedthe bolts 98, engaging with the cars 99 on the main case, securing itfirmly in position, and 101 is a single nut in the flat base forsecuring the rock-drill in position on a bolt, on a tripod, or othersuitable support. The nut may have a collar 102 to prevent removal andloss. When the drill is in operation and it is desired to remove thebit, as for the purpose of substitutinga longerone, the bit-nut is firstloosened and drillshell is then fed back, withdrawing the chuck from thebit and leaving the latter in the hole. The two bolts 98 98 on one'sideare withdrawn. The complete rock-drill, tilted to one side or the otherinto the position shown in Fig. XI, clears the bit in the hole, which isthen withdrawn therefrom and replaced with a new or longer bit. Therock-drill is then turned to position. The bolts 98 98 are replaced,securing the drill to its base-plate. The chuck is then turned toclamping position to engage the bit, and the bit-nut is then tightened.By this arrangement the base-plate remains fixed and the bit is easilyremoved and replaced without danger of disarranging the alinement, thecomplete rock-drill being swung back on the base-plate necessarily intotrue alinement. With our base-plate the drill may be swung in onedirection or the other, which may be necessaryin case of a side breastorwall. In Fig. VI are shown handles 103 103 on each side for moving thecomplete drill. On one side they are shown in idle position and on theother raised against the stops 104.

Double drill.-Without substantial change by simple modification in thearrangement of parts and by adding suitable connections, shafts, andpinions two drills may be combined with one motor and operated therebywithout greatly increasing the size of the double rock -drill or theoperating power. Such an arrangement is shown in Figs. XIV to XVIII,practically diagrams indicating suflicientl y the arrangement of partsand connections where the motor-case A is arranged between the integralextensions or hoods J J on each side, provided with ways K K for thedrill-shells, which are fed forward therein, carrying the bits, rams,operating-cams, &c. 11 is the tubular armature-shaft carrying pinion X,meshing with intermediate pinion 75 and 76 76, by which, through shafts77 77 and tubular telescoping shafts 78 78 and pinion 17, keyed thereto,the driving-cam shell and driving-shell are rotated. As here shown, theextensions J are arranged on each side of the motor-case, and thedrill-shells arranged therein are brought back nearly to the rear of themotor-case, by which the length of the complete rock-drill is less thanthat of the single drill, though it is necessarily widened IZC toreceive the duplicate parts for sustaining and operating the rams andbits. The pinion X is then secured onthe rear of the motor to, a singlesolid armature-shaft instead of to the front of the motor, and shafts 7777 and 78 78 correspond to. shafts 11 and 15 in thesindrill is shownsupported on a quarry-bar .of usual construction, having a rack andadjusted thereon by handle 81. The feed- I screws L Lare rearwardlyextended, attording bearings for the cranksF F and their tubular shaft40 40 and gears 41 41 having the crankclutches 82 82, which may be movedinwardly to engage with screw-clutches S3 83 on the screw-gears 63 63,secured onfeed-screws with which mesh gears 84 84 on correspondingcounter-shafts 85 85, which may be connected to rotate together byclutch member 86, keyed fast on the counter-shaft, and clutch member 87to slide on the other andmoved into and out of engagement by lever 88e11- gag'ing in groove 89. When counter-shaft clutches are out ofengagement, either drill may be fed without feeding the other, or both Idrills may be fed simultaneously, but independently, by their respectivecranks and at different rates, if desired. By the engagement of thesecounter-shaft clutches the two drills may be fed together uniformly byeither crank. When the cranks are moved into their out position, theirgears 41 41 engage with gears 90 90 on vertical shafts 91 91, havingdouble bevel-gears 92 92 on their lowerends, with which engagebevel-gears 45 45 on solid shafts 46 46, connected by telescoping shafts47 47, by which through gears 49 49 and through connections the cams areseparated before the motor is started, and the engage -ment of the camstherefore regulated. Crossshaft-93', parallel to counter-shaft 85 85,has beveled gears 94 94, meshing with gears 92 92, and a central gear 95to engage with the fiber-gear a to operate the switch 70 throughclutch-collar c andpawl d to turn on the currentsafter the cams havebeen separated, ex-

a-s hereinbefore described in the'single To arrange the connections tooperate the bits alternately is better than to operate them"simultaneously, requiring less total power and current. v

U7zaracteristies.--We are aware that it has been proposed to combine anelectric motor and a rock-drill, but with-direct connections or with ramand other parts reciprocating through'the-magnets, thus disarranging theelectrical and mechanical action of the motor and rendering it necessaryto feed the motor and drill together on extended supports. In our devicethe motor and drill are combined and inclosed in one case, making asingle compact comparatively light rock-drill, 1

easy to transport and arrange in position, in

which all the parts are inclosed'and 'pr'otectetl from injury and damp,and motor and drill are so separated, being connected by variable shaftsand indirect operative connections with ,the connections andreciprocating parts entirely outside of the motor, thatthe motor cannotbe injured mechanically by vibration or shock from the drill tending tojar armature and coils, shake out the insulation, data, nor disturbedelectrically, causing heating, variation in lines of force, and inpower. case remain stationary,while the drill is fed independentlyin theextension withoutsubstantial change in the center of gravity and withoutthe use of a heavy and clumsy auxiliary standard with longguideways,making our complete rock-drill simple, compact, and stable.The current, adjustment of cams, and

At the same time the motor and main feed are all controlled and operatedby a single crank and without stopping the drill. The

length of the stroke may be quickly and easily changed,'necessary inseamy and conglomerate rock. The stroke may be varied from the shortestto full stroke by smallest Variations and easily and gradually varied toget'correct length of stroke, and at any length of stroke the rotationof bit is positively and too independently effected to present thecutting.

edge of the bit in a new position to' the rock By the base-plate"thecomat each stroke.

plete rock-drill is supported solidly with a) low center of gravity andeasy removal and renewal of bit is permitted. It is simple and t,

economical to make'and operate.

It is eas to assemble and disassemble.

A compact mechanism for controlling the current is'pro vided. The-caseand housing faresubstan tially cylindrical, so as to be easilyfftnad'eturned, and finished. While our rock;

is particularly devised to be used with a electric motor, which isgenerally more con: venient, the power being supplied from a distance byordinary wires, yet other power may be substituted where desired withoutsubstantial change in the parts of the drill.

WVhat we claim as our invention, and desire to secure by Letters Patent,is.

1. In a percussive rock-drill, the combination of a suitable support, amotor thereon sustained in a fixed position, an'exten'sion on thesupport provided with 'ays,drilling mechanism fitted on the ways, apercussion-spring, intermediate variable connections, between the motorand the drilling mechanism, to re-' tract the drill against the force ofthespring, mechanism inf and means feeding the drilling. dependently ofthe motor.

2. In a percussive rocledrill, the 'combina f tion of a suitable supportprovided with ways, an electric motor'on the support, percussivedrilling mechanism fittedon theway's,

. lindrical case, a motor arranged within the case, an extension on thecase provided with ways, a drilling mechanism fitted to the ways,variable connections between the motor and the drilling mechanism, saidconnections having a sliding step-by-step movement to operate thedrilling mechanism at different distances from the motor as'saidmechanism is fed, and means feeding the drilling mechanism step by steponthe ways independently of the motor.

4 In a rock-drill, the combination of a suitable support, a motorarranged on the support, an extension on the support provided with ways,a drill-shell fitted to the ways,

drilling mechanism arranged in the drillshell, variable operativeconnections between the motor and the drilling mechanism, and

' means for-feeding the drill-shell on the ways independently of themotor, while the motor maintains a constant position on the support.

- 5. In a rock-drill, the combination of a suitable inclosing case, amotor arranged in a chamber within the case, a drilling mechanism fittedin ways in said case, a percussionspring, variable operative connectionsbetween the motor and the drilling mechanism for retracting the drillagainst the force of the spring, and means feeding the drillingmechanism on the ways at varying distances from the motor.

6. In a rock-drill, the combination of an integral support, an electricmotor arranged -therein having an armature and armaturesupport. 1

7. In a rock-drill, the combination of an electric motorhaving anarmature-shaft suitably jonrnaled in the support, a percussive drillingmechanism carrying the ram and bit, variable, operative connectionsbetween the armature-shaft and the drilling mechanism, means for feedingthe drilling mechanism while the motor remains in constant position, theram and bit being arranged to operate parallel to the armature-shaft,and a single suitable support for the motor and drilling mechanism.

8. In a rock-drill, the combination of an integral supporting-case, anelectric motor arranged therein having an armature and armature-shaftsuitably journaled in the case, an integral extension on the supportprovided with ways, a percussive drilling mechanism carrying the bit,said mechanism being'arranged in said extension and fitted to move inthe ways at varying distances from the motor, variable, operativeconnections between the armature-shaft and the drilling mechanism toretract the bit and attached parts, and means to feed the drillingmechanism onthe ways, while the motor maintains a constant position inthe case, the parts being so arranged that the movement of the bit andattached parts and the feed of the drilling mechanism are parallel tothe armature-shaft.

9. In a rock-drill, the combination of a suitable case, a motorsupported therein, a drilling mechanism fitted'in ways on-the case,

variable connections between the motor and drilling mechanism, and meansfor rotating the drill through an arc of constant length at eachstroke,independen tly of the length of the stroke.

10. In a rock-drill,the combination of a suitable case, a motorsupported therein, a drilling mechanism fitted in ways on the case,

variable connections between the motor and I entirely outside of themotor and independ ently thereof, a percussion-spring, variable slidingconnections between the drill and motor to retract the drill against theforce of the spring, and means feeding the drill and said mechanismindependently of the motor.

12. In a rock-drill, the combination of a case provided with ways, anelectric motor in the case, an armatu re-shaf t j onrnaled in the case,a main shaft connected to rotate with the armature-shaft, percussivedrilling mechanism fitted to said ways, intermediate connections betweenthe main shaft and the drilling mechanism, said drilling mechanism andintermediate connections being entirely outside of the motor, and meansfor feeding the drilling mechanism independently of the motor.

13. In a rock-drill, the combination of a case provided with ways, anelectric motor in the case, an armature-shaft, a main shafttelescopically connected to the armature-shaft and rotating therewith,percussive drilling mechanism fitted to said ways, intermediateconnections between the main shaft and the drilling in. chanism, saiddrilling mechanism and intermediate connections being arranged entirelyoutside of the motor, and means for 'feeding the drilling mechanismindependently of the motor.

operate percussively the drill, consisting of a ram, ram-cam, mainspringand driving-cam, suitably supported and fitted to the ways, variableconnections between the motor and driving-cam, means to feed the drilland said percussive mechanism on the ways independently of the motor,means to regulate the distance between the cams and means for turning onthe power.

15. In a rock-drill, the combination ofasuitable case, a motorsupportedtherein, a drill tag mechanism fitted in ways on the case, saidmechanism consisting of a drill, a ram-cam, almainspring anddriving-cam, suitable connections between the motor and drilling mechanism, and a single crank and connections for separating the cams andturning on the power.

' 16. Inarock-drill, thecombination ot'asuitable case, a'motorsupportedtherein, a drilling mechanism consisting of a drill, a ramcam, amainspring and drivlng-cam, suitable connections between the motor anddrilling mechanism, a single crank and connecvlions for separating thecams, turning on the power, and bringing together the cams and separateconnections for feeding the drill independently of the motor.

-17, The combination in a rock-drill, of a main case provided with ways,a motor supported in the case, a drill-shell fitted to said ways, a ram,ram-cam, bit and mainspring suitably supported in the drill-shell, adriving-cam also supported in the drill-shell and engaging with theram-cam, variable connections between the motor and driving-cam, asinglecrank adapted to be arranged indifferent positions, connectionsbetween the crank in one position and driving-cam to separate the cams,means operated by the crank in the same position to turn on the power,and connections between the crank in a second position and thedrill-shell to feed said shell and the parts supported therein.

18. In combination in a rock-drill, a substantially cylindrical maincase, an electric motor arranged therein, a tubular armatureshaftjournaled in the case carrying the armature, a diiving shaft connectedto theja'iy.

' mature-shaft to rotate therewith butcapable of independentlongitudinal movement, an extension on the case, a drill-shell fittingthe extension, the bit and mechanism to efiect percussive reciprocationthereof and attached independently of the motor.

motor without changing the, position of the motor. 7

19. In combination in a rock-drill, a main case, a motor journaledtherein, an extension on the case having ways, adrill-shell fitted toreciprocate in said ways; mechanism arranged in the drill-shell toeffect the blow of the bit, said mechanism consisting of the bit, ram,ram-cam, and mainspring; adrivingcam also in the drill-shell andengaging with the ram-cam, variable connections between the motor anddriving-cam to rotate the driving-cam to retract the bit, and means toreciprocate the drill-shell and inclo sed parts 20. In combination in arock-drill, a case, an electric motor arranged therein, a tubular shaftsuitably journaled in the case and carrying the armature, an integralextension on the case, a drill-shell fitted to move on ways in saidextension, a bit arranged to reciprocate percussively in thedrill-shell, variable connections between the armatnre-shattand the bitto operate the bit and to transform the rotary motion of the motor intothe reciprocating motion of the bit, said mechanism consisting of a ram,a mainspring engaging therewith, a ram-cam on the ram, a ram-cam shellrotatably connected to the ram-cam, a driving-cam engaging with theram-cam, a driving-cam shell rotatably connected to the driving-cam, agear on the driving-cam shell, a drivingshaft rotatably connected to thearmatureshaft, and intermediate pinions connecting the driving-cam shellto rotate with the driving-shaft.

21. The combination, in a rock-drill, of an -inclosing case, an electricmotor arranged therein, an extension on the case,,a bit'and mechanismarranged in the extensionto percussively reciprocate the bit and itsattached parts, a percussion-spring, and variable'sliding connectionsbetween the motor and said mechanism to retract the drill against theforce of the spring, all of said reciprocating parts being arrangedoutside of the motor.

22. In combination in a rock-drill, a main case, an electric motorarranged therein having the armature supported ona tubularshaft suitablyjournaled in the case, said ttubular shaft, a driving-shaft connected tothe armatare-shaft to rotate therewith but capable of independent,longitudinal movement, an integral extension on the case, a bit, aramand ram-cam arranged percussively to reciprocate in the extension andentirely outside of' the motor, a rotating driving-cam to-retract,

theram-cam and attached D and:M15917v mediate variable connectionsbetween the driving-shaft and driving-cam to rotate the driving-cam. g

23.. In combination in a rock-drill, a main case suitably supportedhaving an integral extension, a rotary motor journaled in the main.case, a drill-shell fitted to ways in said extension, a ram, a bit, aspring or springs,

a ram-cam and a driving-cam carried in the drill-shell,variable'conneotions between the motor and the driving-cam, means forrotating the bit through an arc of constant length at each strokeindependently of the length of the stroke, and means for feeding thedrillshell in the extension independently of the motor.

24. In combination in a rock-drill, a main case, an integral extensionthereon, a motor arranged in the case, a drill-shell fitted to theextension; a bit, a ram-cam, mainspring and driving-cam arranged in thedrillshell,means to feed the drill-shell in the extension independentlyof the motor, variable connections between the motor and thedriving-cam, and

'means to regulate the distance between the cams.

25. In combination in a rock-drill, a main case, an integral extensionthereon, a motor arranged in the case, a drill-shell fitted to theextension, a bit, ram, ram-cam, and mainspring and driving-cam arrangedin the drillshell, means to feed the drill-shell in the extensionindependently of the motor, variable connections between the motor andthe driving-cam, means to regulate the distance between ,the cams, toregulate the length of stroke, without stopping the drill, and means torotate the bit and attached parts a fixed distance at each stroke,independently of the length of stroke.

26. In combination in a rock-drill, a substantially cylindrical casesuitably supported having extensions, a rotary motor journaled on atubular shaft in the case, drill-shells fitted to ways in theextensions, a ram, a ramcam, a bit, an operating spring or springs and adriving-cam carried in each drill-shell, and variable connectionsbetween the motorshaft and the driving-cams.

, 27. In combination in a rock-drill,a case,an' electric motor arrangedtherein, a suitable switching mechanism to turn on the current;

an integral extension on the case, a drill-shell fitted to ways in theextension; a ram, bit and mainspring in the shell, a ram-cam on the ram,a ram-cam shell rotatabl y connected to the ram-cam; a driving-cam and adriving-cam shell rotatably connected; a retracting-sheil fitted withinthe drill-shell, means connecting the driving-cam to move longitudinallywith the retracting-shell; variable connections between thearmature-shaft and the driving-cam shell; a single crank adapted to bearranged at will in one of two positions, connections between the crankin one position and the retracting-shell to vary the distance betweenthe cams, other connections between the crank in the same position andthe switching mechanism to turn on the current after the cams have beenseparated, and connections between the crank in the second position andthe feed-screw to feed the drill.

28. In combination in a rock-drill, a suitable case, an electric motorarranged therein, a tubular shaft journaledtherein carrying tionsbetween the armature-shaft and the" driving-cam shell,and means to feedthe drillshell with inclosed parts while the rock-drill is in operation.

29. In combination in'a rock-drill, a substantially cylindrical case, anelectric motor arranged therein, having an armature-shaft journaled inthe case, an integral extension on the case, a drill-shell fitted toways therein, a ram, bit and mainspring in said shell, 9. ram-cam on theram, a ram-cam shell rotatably connected to the ram-cam, a driving-camand a driving-cam shell rotatably connected thereto, a retracting-shellto fit within the drill-shell and connected to the driving-cam to movethe driving-cam longitudinally, means for rotating the bit and ramindependently of the length of the stroke,variable connections betweenthe armature-shaft and driving-cam shell, a single crank, one set ofconnectingshafts and gears between the crank and the retracting-shell tovary the distance between the cams, a feed-screw mounted in the case andconnected to the drill-shell, and a second set of connections betweenthe crank and the feed-screw to reciprocate the drill-shell on the ways.

30. In combination in a rock-drill, a substantially cylindrical case, anelectric motor arranged therein, a shaft suitably journaled for thearmature, an integral extension on the case, a drill-shell fitted toways therein, a ram, bit and mainspring in the shell, a ram-cam on theram, a ram-cam shell rotatably connected to the ram-cam, a driving-camand a driving-cam shell rotatably connected thereto, a retracting-shellto fit within the drillshell, means connecting the driving-cam to movelongitudinally with the retracting-shell, means rotating the bit and ramindependently of the length of the stroke, variable connections betweenthe armature-shaft and the driving-cam shell, a single crank adapted tobe arranged in one of two positions and locked in either position atwill, connections between the crank in one position andtheretractingshell to vary the distance between the cams, a feed-screwjournaled in the extension and connected to the drill-shell, and asecond set of connections between the crank in the second position andthe feed-screw to feed the shell.

31. In combination in a rock-drill, a subvstantiallly cylindrical case,-anelectric motor arranged thefeim'a tubular shaft suitably journaled forthe -a-rmature,,an integral ex tension on the case, a drill-shell fittedtoways in the extension, a ram, bit and mainsp'ring in said shell, aram-cam, on the-ram,;.a ram cam shell rotatably connected to theram-cam,

a driving-cam and-a driving-cam shell rotata--' moving theretractingshell to varythe dis-- tance between "the cams, meansfor-feeding the drill-shell and the bit, means for rotating the bit, afixed distance at each stroke independently of thelength of thestroke,.variable connections between, the armature-shaftanddrivi-ng-cam shellconsisting of a telescoping'shaft rotatably connected to the tubulararmature-shaft, agear on-sai'd telescopiug shaft, a gear on the exteriorof .thedriving-cam shell, and an intermediate gear suitably journaled inthe drill-shell and meshing with said shaft-gear and said driving-shellgear.

motor arrangedtherein, a tubular-armature v shaft j ournaled thereincarryingth'e armature of themotor; an. integral extension on thecaseformed with ways, a drill-shell, fitted to said, ways, a rear plateto the drill-shell and a hollow nut screwed to its front end, a ram, a

chuck, and a bit'secured on the ram, a hollow flanged collar secured 'onthe ram adjacent tothe'chuck and fitting within the hol 'low' nut, abuffer-spring arranged between said flanged collar and the nut; anabutment in the drill-'shelha mainspring arranged aroundjthe ram betweensaid abutment and the hollow Gollar; a ram-cam onthe rear end of therain, aram-cam shell, afeather'co'nnectingthe ram-catnand its shell-aterotate togetherbut to reciprocate independently; a driving-cam and adriving-cam shell, a feather connecting the driving-cam and its shell torotate togetherbut toreciprocate independently ,'a' retractin g-shellthreaded :to fit within the drill-shell, to be moved longitudinallytherein, a shank and nut connecting the driving-cain to reciprocate withsaid retractingshell, gear on the retracting-shell; a gear on thedriving-cam shell, a driving-shaft connected to rotate with the tubulararmatureshaft and to slide longitudinally therein, a gear on thedriving-shaman intermediate pinion'meshing with said dri'ving-shaft gearand the driving-cam-shell gear; a feed-screw journaled in the.extension, an integral nut on the drill-shell engaging withxthefeedscrew, and a feed-screw gear on the feedscrew; an extension on therear of the main shell inclosing connections for the line-wires, and asuitable switch for gradually turning 32. In combination in arock-drill, a sub- 1 stantially cylindrical main case,:anelectr ic,

on the current; a stud arranged in said chaniber formed with twogrooves, a tubularcran-b shaft jourualed and sliding on said stud, agear on the inner end of said cran k-shafzt, and

a cran'k'on its ou'terend, a latchon 'saidcrank adapted to engage withthe 'stud-groovesand tolock the crankand gear-in 'u-t' tion at will; asolid shaft jo lower portion of the case, a rearg toengagewi-thcrank-gear in i I a telescoping shaft, an intern late pinionmeshingwith said front gear and the, retracting-shell gear; a tubularshaft in'closiug said solid and telescoping shafts, a rear gear on u theit-rposition,

said tubular shaft to engage with the crankgear in its in posit-ion, afront gear onsaid tubular shaft, intermediate pinions between said frontgear and said feed-screw geaiyand,

connections between the crank-shaft gearin its out position and theswitch gradually to turn on the current, substantially as shown anddescribed.

- 33. In a percussive rock-drill means for.

turning the bit through an arc of constant length at each strokeindependently of the length of the stroke, havingin combination asuitable inclosiug shell, a driving-cam and drivingcam shell, aconnection between saidcam and shell by which they are connected torotate together but free toreciprocate independently, means'for rotatingsaidshell, a bit,-ram, ram-cam, ram-cam shell andmainspriugalsoin'closedintheinclosingshell,aconnection between saidrain-cam and its shell whereby they are connected to rotate together.but to reciprocateindependently, abutments on said shells engaging ateach 'rotation and rgthereon forcing the ram-cam shell rearwardly,.aspring.

tending to force said ram-cam shellforward, said ram-cam shell beingformed with. a -continuous circumferential series of inclines, andsubstantially fixed projections within thecase engaging with saidinclines when'flrarn-cam.

shell is forced rearwa'rdly.

3t. Injcombination in a percussive-rockdrill, a main case, a motorinclosed-thereim an extension on the case formed with Ways,a drill-shellfitted to said ways, a bit,,ra1n'.and' spring,'a maindriving-camanddrivingcam shell, a main ram-cam and ram-cam shellin-'closed in the drill-shell, connections between eachlmain cam anditsshell whereby therespective cams and shells rotate together but arefree to reciprocate independently,-variable connections between themotor and the driving-cam shell, small camson theiadjacent edges of thecam-shells having each an inclined edge and flatface engaging at eachrotation of the driving-cam shell andar- -ranged to disengage at thepoint of, disengagement of the main cams, saidram cam shell being formedtoward the rear-"withia circumferential series of short inclines ofequal length, substantially fixed abutments in the driving-shell toengage with said inclines when the ram-cam shell is forced rearwardly,and a spring or springs to force said ram-cam shell forwardly, wherebythe bit is turned through an arc of fixed length at eachstroke-independently of the length of the stroke. a

, 35.1In a percussive rock-drill, a main case and suitable supports, amotor, a driving-cam and driving-cam shell connected to rotate togather,but reciprocating independently, connections between the motor and thedrivingcam to rotate said cam; a bit, a ram, a ramcam and .mainspring, aram-cam shell connec'ted to the ram-cam to rotate therewith but toreciprocate independently; and means rotatably to shift the ram-cam,ram, and bit a constant distance at each stroke independently of thelength of the stroke, having in combination small cams on the cam-shellsing rearwardly, a shifting shell having corre-v adapted to engage ateach rotation of the driving-cam shell; acircumferential series ofinclined teeth onthe ram-cam shell extendspending teeth reverselyarrange and adapted to engage with said ram-cam-shell teeth when theram-cam shell is forced earwardly by the engagement of the small ams,fixed studs to engage with short slots on the rear of the shifting shellpermitting said shifting shell to be turned a short distance by theengagement/of the ram-cam shell, and a spring toreturn the shiftingshell to normal posi-- tion when out of engagement with the ramcamshell.

36. Ineombination in a rock-drill asubstantial'ly cylindrical case, amotor and drill inclosed therein, pairs of integral perforated '1 earscorrespondingly arranged on the lower portionot the case, one pair oneach 'side, a

' hase-plate having pairs of forwardly-extending perforated armscorresponding to said ears,- and removable bolts for connecting the earsto their respective arms, whereby the en- I tire case with the inclosedmotor and drill may be rocked to one side or the other and returnedpositively to operative position.

37. In combination in a rock-drill, a cylindrical case having a forwardextension, a motor and drill inclosed respectively in the case andextension, pairs of integral, perforated ears arranged one pair on eachside of the lower portion of the case, a supporting baseplate having asubstantially flat base and pairs of forwardly-extending perforated armsarranged one pair on each side corresponding side or the other andreturned positively to'65 39. In combination in a rock-drill, asubstantially cylindrical case, a motor inclosed therein, integralextensions on each side having ways for the drill elements, adrill-shell arranged in each extension and movable longitudinally on theways; a ram, bit, mechanism for elfecting percussive rotation thereof,mainspring, ram-cam and driving-cam arranged in each drill-shell,variable connections between the motor and each drivingcam; two crankssuitably journaled on the rear of the case and adjustable each in twopositions, connections between .both cranks inone position and thedriving-cams 'to vary the distance between the cams, and otherconnections between both cranks and an electric switch mechanism to turnon the current when the cams are separated; feed-screws suitablysupported, and connections between said feed-screws and their respectivedrillshells to feed the drill elements, connections between each crankin its second position and-- the corresponding feed-screw to operate thescrew, and adjustable connections between said cranks whereby each shellmay be fed independently, by its own crank or both shells fed togetherby either crank.

40. In combination in a rock-drill, a main case, an electric motorarranged therein, a suitable shaft for the armature, an extension on thecase, a drill-shell arranged to be fed in said extension,a reciprocatingram, 3. bit and ram-cam secured to the ram, a mainspring, mechanism toretract the ram, bit and ram-cam against thespring, a driving-shaftkeyed to rotate with the armature-shaft and free to move in and outthereon, indirect connections between said driving-shaft and saidretracting mechanism consisting of suitable gearing, said reciprocatingparts and indirect connections being entirely outside of motor and ofmain case.

In testimony whereof we have signed our names to this specification inthe presence of two subscribing witnesses.

HENRY D. CRIPIEN. GEORGE WHITE. GEORGE S. MAXWELL.

Witnesses:

ALFRED WILKINSON, CAROLINE L. CUE.

